In recent years, power storage devices such as lithium-ion secondary batteries, lithium-ion capacitors, and air cells have been developed.
An electrode for the power storage device is manufactured by providing an active material over a surface of a current collector. As the active material, a material which can adsorb and release ions functioning as carriers, such as carbon or silicon, is used. For example, silicon or phosphorus-doped silicon has an advantage of larger theoretical capacity than carbon and larger capacity of a power storage device (e.g., Patent Document 1).